کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5189705 1381190 2007 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Electrospray ionization mass spectrometric end-group analysis of PMMA produced by radical polymerization using diacyl peroxide initiators
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Electrospray ionization mass spectrometric end-group analysis of PMMA produced by radical polymerization using diacyl peroxide initiators
چکیده انگلیسی
The type and number of end groups of poly(methyl methacrylates) from free-radical polymerization with six diacyl peroxides, R-(CO)O-O(CO)-R, acting as initiators have been analyzed via electrospray ionization mass spectrometry using an ion trap and additionally Fourier transform ion cyclotron resonance for mass detection. The polymerizations were carried out in benzene solution at high initiator concentration to yield low molecular weight polymer. With R being an alkyl group, only R moieties are observed as end groups. For each oligomer size, molecules with one or two such end groups are formed, depending on whether termination occurs via disproportionation or combination. With R being an aryl type, as in di-benzoyl and di-naphthoyl peroxides, both R and R-(CO)O moieties are detected as polymeric end groups. Because of aromatic delocalization, fractions of the arylic R-(CO)O radicals are sufficiently long living at 95 °C to add to a monomer molecule prior to undergo decarboxylation.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer - Volume 48, Issue 19, 10 September 2007, Pages 5590-5598
نویسندگان
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